1. Field of the Invention
The present invention relates to a design assistance device, a design assistance method and a recording medium for a liquid ejection device, a method of manufacturing a liquid ejection device and an image recording device, and more particularly to a technique of applying pressure fluctuation into a print head by using a pump to supply and circulate ink.
2. Description of the Related Art
In an ink jet recording device, stable supply of ink to a print head is required to accurately control the ejection of ink from nozzles of the print head, and the “stable” described herein means that pressure fluctuation is reduced as much as possible. The pressure fluctuation may affect image quality, concentration, and ink drop position accuracy.
In a case of an ink supply system by a water head method, there is no pressure fluctuation in feeding liquid itself. However, in a case where a pump method is adopted, there is a possibility that pressure largely varies due to pulsation caused by a pump, so that the pressure cannot be appropriately controlled.
As above, in the pump method, a frequency of a flow rate source of the pump is determined in accordance with a rotation speed of the pump. Thus, it is required to determine design values of a damper and a flow channel so that amplitude strength at a frequency at which predetermined pump drive is performed is sufficiently reduced.
In contrast, PTL 1 (Japanese Patent Application Laid-Open No. 60-171163) describes a technique in which there are provided a first portion including a piezoelectric converter for ejecting a droplet from a nozzle, and a second portion made of viscoelasticity material that absorbs energy of a pressure wave propagated in a duct, and in which the second portion is connected to a liquid pressure resistance to attenuate resonance of the duct at a frequency lower than a cutoff frequency, and a size of the second portion is adjusted to attenuate resonance of the duct at a frequency higher than the cutoff frequency.